in utero Syllabification: (in u·ter·o)Pronunciation: /in ˈyo͞otərō/Definition of in utero adverb & adjective in a woman’s uterus; before birth: [as adverb]:this damage may occur in utero [as adjective]:the in utero development of the gastrointestinal tractOrigin:Latinin utero in other Oxford dictionaries Definition of in utero in the British & World English dictionary